According to Boundless, soil is a mix of varying amounts of inorganic matter, organic matter, water and air. The components in soil provide nutrients for plant uptake and can fluctuate on a daily basis, depending on water supply, cultivation practices and soil type.
According to the University of Hawaii, typical soil consists of approximately 45 percent mineral, 5 percent organic matter, 20 to 30 percent water and 20 to 30 percent air. The ratio of air and water in the pore spaces often changes seasonally depending on the amount of precipitation and groundwater discharge. The mineral, or inorganic, portion of the soil consists of three particle-size classes: sand, silt and clay.
According to National Oceanic and Atmospheric Administration, sand, silt and clay are less than 2 millimeters in diameter. These particles are collectively referred to as the fine earth fraction soil, whereas larger particles, such as pebbles, cobbles and boulders, are referred to as rock fragments. The organic matter in the soil consists of a complex mixture of substances with varying chemical contents. The elemental composition of organic matter includes carbon, oxygen, hydrogen, nitrogen, phosphorus and sulfur. According to Boundless, the organic material of soil, called humus, is also made up of microorganisms and dead animals and plants in varying stages of decay.Learn More
Sand is primarily composed of finely granulated silica and, depending on its location, can include various rock, coral, shell or lava fragments. It is lightweight and easily transported by wind and water. Its composition directly affects its color, resulting in black, white, pink and green coloring.Full Answer >
Sandy soils are granular soils that contain small rock and mineral particles. The texture of sandy soils is usually gritty. This soil feels course whether it is dry or wet.Full Answer >
Soil is created from the erosion of rocks by weather or mechanical processes. Over a very long time, the surface of the rock softens, decays and becomes soil.Full Answer >
The four basic types of soil are sand, silt, clay and loam. Loam, considered a perfect soil, is a mixture of silt, clay and sand. Sand is gritty and contains small particles of minerals and rocks, where silt is smoother than sand and is more fertile.Full Answer >